In its
ninth
flight
(GSLV-D6)
conducted
today,
(August
27,
2015),
India's
Geosynchronous
Satellite
Launch
Vehicle,
equipped
with the
indigenous
Cryogenic
Upper
Stage
(CUS),
successfully
launched
GSAT-6,
the
country's
latest
communication
satellite,
into a
Geosynchronous
Transfer
Orbit
(GTO).
The
achieved
orbit is
very
close to
the
intended
one.
The
launch
took
place
from the
Second
Launch
Pad at
the
Satish
Dhawan
Space
Centre
SHAR
(SDSC
SHAR),
Sriharikota,
the
spaceport
of
India.
This was
the
fifth
developmental
flight
of GSLV
and the
third to
carry
the
indigenous
CUS.
GSLV-D6
was
intended
to
further
test and
qualify
the CUS
developed
by
ISRO.

In its
oval
shaped
GTO, the
GSAT-6
satellite
is now
orbiting
the
Earth
with a
perigee
(nearest
point to
Earth)
of 168
km and
an
apogee
(farthest
point to
Earth)
of
35,939
km with
an
orbital
inclination
of 20.01
deg with
respect
to the
equator.

At 4.8
seconds
before
the
countdown
reached
zero,
the four
liquid
propellant
strap-on
stages
of
GSLV-D6,
each
carrying
42 tonne
of
liquid
propellants,
were
ignited.
At count
zero and
after
confirming
the
normal
performance
of all
the four
strap-on
motors,
the
mammoth
139
tonne
solid
propellant
first
stage
core
motor
was
ignited
and GSLV
lifted
off. The
major
phases
of the
flight
included
the core
motor
burn-out,
strap on
burn-out,
ignition
of the
second
stage,
separation
of the
core
motor
together
with
strap-ons,
payload
fairing
separation,
second
stage
separation,
CUS
ignition
and its
timely
shut
down
after
satisfactory
performance.
Following
this,
GSAT-6
separated
from CUS
about 17
minutes
after
launch.

Soon
after
its
injection
into
GTO, the
two
solar
arrays
of
GSAT-6
were
automatically
deployed
and the
Master
Control
Facility
(MCF) at
Hassan
in
Karnataka
took
control
of
GSAT-6.

In the
coming
days,
GSAT-6's
orbit
will be
raised
from its
present
GTO to
the
final
circular
Geostationary
Orbit
(GSO) by
firing
the
satellite's
Liquid
Apogee
Motor
(LAM) in
stages.
The
satellite
will be
commissioned
into
service
after
the
completion
of orbit
raising
operations,
deployment
of its 6
m wide
sieve
shaped
unfurlable
antenna,
the
satellite’s
positioning
in its
designated
orbital
slot of
83
degree
East
longitude
in the
GSO and
in-orbit
testing
of its
communication
payloads.